IEEE802.11 WLAN多业务综合传输性能分析

Performance Analysis of Integrated Voice and Data Transmission on IEEE 802.11 WLAN

研究了IEEE802.11标准中的多址接入协议(MAC)在数据、语音业务综合传输情况下的性能。数据业务由分布协调功能(DCF)传送,语音业务由点协调功能(PCF)传送。通过仿真,评估了协议参数对网络通过量和平均MAC协议数据单元(MPDU)时延的影响,确定在一定数据通过量前提下IEEE802.11能支持的最大语音用户个数。特别地,语音业务对时延抖动敏感,指出了影响其抖动性能的主要因素。数值结果表明,合理选择参数对性能至关重要,IEEE802.11性能必须在语音站点数量和数据业务通过量之间进行折衷。最后,通过理论推导验证了仿真结果的正确性。

The IEEE 802.11 standard MAC is a hybrid protocol of random access and polling when both DCF (distributed coordination function) and PCF (point coordination function) are used. This (paper) studies the performance of the MAC protocol for integrated data and voice transmission where data traffic is transmitted with the DCF, and voice transmission is carried out with the PCF. By simulation, we evaluate the network throughput and the average MPDU (MAC protocol data unit) delay for various values of the protocol parameters and determine the maximal number of the voice service users on the condition of defined data throughput. Especially, voice traffic is sensitive to delay jitter and here we point out the main influencing factors. Numerical results show that it is important to choose appropriate protocol (parameters) and we should make a compromise between the number of the voice stations and the data traffic throughput to get the enhanced performance of IEEE 802.11. Finally, the performance of protocol is (derived) theoretically, which verifies the correctness of the simulation results.